Reciprocally engageable clutch mechanism

ABSTRACT

A clutch mechanism for reciprocatingly engaging a driven member with a driving member wherein the driven member is biased in one rotational direction and alternately driven over a predetermined arc in the opposite direction. The respective angular positions of engagement and disengagement of the driven member with the driving member are determined by angularly displaced restraining means that actuate an engagement control member carried with the driving and driven members.

United States Patent Mack et al.

[ RECIPROCALLY EN GAGEABLE CLUTCH NIECHANISM [72] Inventors: RonaldMack, Plymouth; Robert H. Wilczewski, Northville, both of Mich.;Nicholas Kondur, Jr., Rolling Meadows, Ill.

[73] Assignee: Burroughs Corporation, Detroit,

Mich.

[22] Filed: Feb. 26, 1971 [21] Appl. No.1 119,170

[52] US. Cl..., .;.192/33 R, 74/1255, 192/14 [51] Int. Cl ..Fl6d 43/00[58] Field of Search 192/33, 14; 74/1255, 118,

[56] References Cited UNITED STATES PATENTS 1,76 5, 5 27 6/1930 Gollnicket a1 ..192/33 R [451 Nov. 28, 1972 3,048,246 8/ 1 962 Paige ..l92/33 RPrimary ExaminerBenjamin W. Wyche Assistant Examiner-Ra.nda.ll l-lealdAttorney-Kenneth L. Miller and Edwin W. Uren ABSTRACT A clutch mechanismfor reciprocatingly engaging a driven member with a driving memberwherein the driven member is biased in one rotational direction andalternately driven over a predetermined arc in the opposite direction.The respective angular positions of engagement and disengagement of thedriven member with the driving member are determined by angularlydisplaced restraining means that actuate an engagement control membercarried with the driving and driven members.

; r 15am, 7 D W SV l EQ T RECIPROCALLY ENGAGEABLE CLUTCH MECHANISMBACKGROUND OF THE INVENTION This invention relates generally to clutchmechanisms and, more specifically, to mechanisms for alternatinglyengaging and disengaging a driven member with a driving member.

A particular need is seen in the printing art for a clutch mechanism ofthe variety herein disclosed.

Many printing mechanisms, and especially those associated with businessmachines or computers print serially across the narrow dimension of apaper strip such as in a common adding machine or cash register. Thestrip paper is driven by feeding means, such as opposing rollers, pastthe printing position in the mechanism. The feeding means must becontrolled to drive the paper from print line to print line according toa particular printing format. Usually the paper is spaced to the nextline as soon as a printed line is completed across the width of thepaper strip.

In some applications it is desirable to print several lines ofinformation identical to that printed on the paper strip on anothermedium such as a document. Such may be the case with an account depositslip in a banking operation where a record of a bank tellerstransactions are normally maintained on the paper strip or roll. When acustomer presents a deposit slip to the teller appropriate informationmust be printed both on the paper strip and deposit slip. To save spaceand cost it is desirable that the document feeding mechanism be commonlydriven by the same means that drives the strip paper. Provision shouldalso be made for beginning the printing operation at varying verticalpositions on the document so as to coincide with the document format andthe particular information to be printed thereupon.

SUMMARY OF THE INVENTION It is, accordingly, an important object of thepresent invention to provide a document feeder option for a strip paperprinting machine that utilizes the same driving means as drives thestrip paper feeder.

It is another important object of the present invention to couple adriven member with a unidirectionally rotatable strip feed drivingmember in such a manner that the driven member is periodically engagedwith and disengaged from the driving member to lift a document insuccessive print lines upon engagement and to return the driven memberto a starting position upon disengagement, thus reciprocating the drivenmember in an arc between two predetermined positions.

It is a related object of the invention to provide a mechanism in whichvariation of the arc of reciprocation of the driven member may be easilyaccomplished.

It is also an object of the invention to effect disengagement of thedriven member by merely restraining its rotational motion.

It is an allied object of the invention to permit adjustment of themagnitude of the restraint necessaryto effect disengagement.

It is a further object of the present invention to provide a compactlyconstructed clutch mechanism for effecting reciprocation.

It is an associated object of the invention to provide a clutchmechanism in which the driven member may be latched in a home positionat a predetermined location within its arc of reciprocation.

In accordance with the invention, a driven member is biased in a secondrotational direction. A portion of an engaging member is displaceableinto engagement with a driving member to drivably couple the drivenmember therewith in a first rotational direction. The engaging member isyieldably biased for resilient angular displacement in the firstrotational direction with respect to the driven member. An engagementcontrol member, that is also yieldably biased with respect to the drivenmember, serves to hold the engaging portion of the engaging member outof engagement with the driving member until such time as the engagementcontrol member is displaced in the first rotational direction withrespect to the engaging member. The engagement control member being sodisplaced, permits the engaging portion of the engaging member to moveinto engagement with the driving member to initiate rotation of thedriven member in the first rotational direction. When the driven memberis restrained while moving in the first rotational direction, theengaging portion of the engaging member cams out of engagement with thedriving member; thus disengaging the driven member therefrom.

BRIEF DESCRIPTION OF THE DRAWINGS To facilitate a'more completeunderstanding of the invention, a preferred embodiment thereof willhereinafter be described in connection with the drawings in which: FIG.1 is a side elevation view showing the preferred clutch mechanismembodied in a printing machine;

FIG. 2 is an exploded view of the preferred clutch mechanism;

FIG. 3 is a detailed orthographic view taken from FIG. 2;

FIG. 4 is a side elevation viewing the clutch clutch mechanism initiallydisengaged.

' DETAILED DESCRIPTION Turning now to the drawings wherein likereference characters designate identical elements in each of the Figuresand, particularly to FIG. 1, there is shown a preferred clutch mechanismembodied in a printing machine. As illustrated, a strip of paper 10 orother such medium is normally moved in the printing machine tosuccessive print lines by the driving action of a paper driving wheel 12and pinch roller 14. The paper strip 10 is guided through a printingposition 16 in the machine by guide rollers 18 disposed radially apartfrom the periphery of the paper driving wheel 12 and in the direction ofpaper feed from the pinch roller 14. The paper driving wheel 12 is oneof three disc-like sectors, all being mutually rotatable about a commonaxis 20. One of the other sectors 22 has a geared periphery that mesheswith a like geared periphery of a driving pinion 24. The driving pinion24, in turn, is controllably rotated to move the paper driving wheel 12at a predetermined speed and for a predetermined interval in order toproperly position the paper with respect to the printing position 16 ofthe machine. During a normal printing operation the driving pinion 24incrementally rotates the geared sector 22 and paper driving wheel 12 sothat after the completion of each printed line the paper strip 10 is fedfor a predetermined distance to the next print line.

A third sector that is mutually rotatable with the paper driving wheeland geared sector is a driving member or ratchet wheel 26. In order thatthe printing machine may optionally print one or more lines ofinformation upon a document 27 as well as upon a paper strip, theinvention provides a driven member or arm 28 that lifts the document 27from print line to print line in conjunction with-the ratchet wheel 26.A document engaging recess 30 on the driven arm 28 servesto position thebottom edge of a document thereupon. In utilizing the document printingoption of the machine an operator depresses a keyed latch 32 thatreleases a bail 34 holding the driven arm 28 in a home position, asshown. The arm 28 is rotated in a second direction or clockwise, asillustrated in FIG. 1, by a return biasing means or spring 36. Thisclockwise rotation causes an engaging portion such as a pivotal pawl 38of an engaging member 40 to pivot into engagement with the ratchet wheel26. With the pivotal pawl 38 thus positioned, the engaging member 40 isdriven a predetermined number of increments in a first rotationaldirection, or counterclockwise, as shown, with the rotating ratchetwheel 26. The engaging member 40 is coupled to the driven arm 28 bymeans of an arm biasing follower or spring 42 so that the rotationalforce of the ratchet wheel 26 is transmitted to the driven arm to raisethe document in the same manner as the paper strip 10 is raised by thepaper driving wheel 12. When the rotation of the driven arm 28 isopposed by a second restraining means or stop 44 the pivotal pawl 38 orthe engaging member 40 is cammed out of engagement with the drivingmember or ratchet wheel 26 in a manner that will hereinafter bedescribed. With the pivotal pawl 38 disengaged the driven arm 28 isrotated clockwise by the return biasing spring 36 until the bail 34engages the keyed latch 32 at the home position of the driven arm.

A reset arm 46 is provided to actuate the displacement of the driven arm28 to the home position whenever the document 27 has been lifted in thefirst rotational direction beyond that position. This feature permits anoperator to reset the driven arm 28 when the desired printing operationon the document is completed before the document has been lifted to itsmaximum height rather than having to wait for the driven arm to pivotall the way to its rotational limit before it is restored. v

The mechanism that couples the driven member or arm 28 to the drivingmember or ratchet wheel 26 may generally be described as a fractionalengagement clutch wherein the driven member 28 is drivably engaged for afractional portion of full rotation with the driving member 26.Disengagement of the driven member 28 is effected by restraining therotational motion of the driven member 28 to initiate the displacementof the engaging member or pawl 38 from the driving member 26. Biasingmeans such as a spring 36 returns the driven member 28 to apredetermined angular position whereupon the engaging member 40 isdisplaced back into engagement with the driving member 26 to continue anunbroken reciprocal chain.

Reciprocation may be interrupted by intercepting and restraining thedriven member 28 as it returns in the second rotational direction, asearlier described in connection with the keyed latch 32 and bail 34(FIG. 1

Describing the clutch mechanism now in greater detail, with reference toFIG. 2, an extension 41 of the driven member 28 on which is formed thedocument engaging recess 30 projects from an annular sleeve 48. Theinner diameter of the sleeve is of such a dimension that it freelyrotates about a shaft 50 of the driving member 26 upon which it ismounted. The bail 34' (shown in FIG. 1 that holds the driven member 28in the home position engages the driven member by means of bail engagingstud 52. A fastener finger 54 and a fastener opening 56 of the-drivenmember 28 serve to respectively attach the arm biasingspring 42 and acontrol member biasing spring 58 thereto. One end of the return baisingspring 36 is attached to a connector opening 60 in the extension 41 ofthe driven member 28. g

The engaging member 40 has an annular sleeve 62 that fits loosely aboutthe outer periphery of the sleeve 48 of the driven member 28. The drivenmember 28 and the engaging member 40 assume a torsionally tensionedrelationship due to the force of the arm biasing follower or spring 42that interconnects the two members. A slot 64 in the sleeve of thedriven member 28 is engaged by a stop (not shown) in the inner peripheryof the sleeve 62 of the engaging member, thus holding the two membersangularly apart in a predetermined axial relationship. An arm 66 of theengaging member 40 carries a pivot shaft 68 for pivotally mounting theengaging portion or' pivotal pawl 38, the pawl being biased in anengaged or counterclockwise position by a torsion spring, as shown inFIGS. 2 and 3'. A limit to counterclockwise rotation of the pivotal pawl38 is established by abutment of an edge section 70 of an engagementcontrol member 72 with a lip 74 of I the pivotal pawl 38. Two opposingwalls 76 and 78 of the pawl 38 form a slot 79 through which a cammingsector 80 of the engagement control member 72 projects to assist inmaintaining the camming section 80 in proper spatial relationship withthe pawl. The slot 79 is terminated at respective ends by a driven camor camming shaft 82 and a cam engaging means such as a roller 84.

The engaging portion or pawl 38 of the engaging member 40, being biasedinto engagement with the driving member or ratchet wheel 26, ismaintained in a disengaged pivotal position by the action of theengagement control member 72. The engagement control member 72 ispositioned between the engaging member 40 and the driven member 28 andis loosely mounted to rotate on the sleeve 48 of the latter member. Acontrol member biasing means such as a spring 58 biases the cammingsector 80 of the engagement control member 72 at a limited or disengagedposition such that a cam engaging edge 86 of the camming sector cams theroller 84 of the pivotal pawl 38 downwardly, as shown. A projection 88on the sleeve 62 of the engaging member 40 serves to limit the rotationof the engagement control member 72 in the first rotational direction byblocking a step 90 on the inner periphery thereof.

The operation of the invention may be more readily understood withreference to FIGS. 4-7, where there is shown the driven member 28 biasedpivotally in a second rotational direction (or counterclockwise, asshown) by the force of the return biasing spring 36. With the pawl 38pivoted out of engagement with the ratchet wheel 26, the return biasingspring 36 is effective to pivot the driven member 28 counterclockwise,as shown in FIG. 4. Such action may be initiated by the depression ofthe keyed latch 32 (FIG. 1) that normally holds the driven member or arm28 in the home position, as hereinbefore described. As the returnbiasing spring 36 rotates the driven arm 28 counterclockwise a stopengaging extension 91 of the engagement control member 72 meets a firstrestraining means or stop 92, thus limiting the pivoting motion of thecontrol member in the second rotational direction, as shown in FIG. 5.With the rotation of the control member 72 restrained, the biasing forceof the return biasing spring 36 continues to pivot the driven member 28in opposition to the biasing tension imposed between it and theengagement control member 72 by the control member biasing spring 58. Asthe engaging member 40 and pawl 38 are rotatably coupled by the armbiasing follower spring 42, the pawl 38 is carried counter clockwisewith respect to the now stationary engagement control member 72 until alimit arm 94 of the driven member 28 contacts the first stop 92. At thispoint the camming sector 80 of the engagement control member 72 ispositioned completely free of either end of the pawl slot 79 throughwhich it extends, thus enabling the torsion spring to pivot the pawl 38counterclockwise, as shown in FIG. 5, into engagement with the ratchetwheel 26. With the pivotal pawl 38 in such a position, the driven member28 is then drivingly coupled with the driving member or ratchet wheel 26through the arm biasing spring 42 that couples the engaging member 40with the driven member 28.

The engaging portion or pawl of the engaging member 40 is held inengagement with the ratchet wheel 26 not only by the pivoting force ofthe torsion spring, as heretofore described, but also by acounterclockwise moment of force applied to the pawl 38 by the drivingforce of the ratchet wheel. This advantageous result is obtained bypositioning the pivot point or shaft 68 of the pawl in an offsetrelationship with the resultantdirection of the force applied by theratchet 26 to the pawl 38. Still another factor that assists the pivotalpawl 38 in remaining engaged with the ratchet wheel 26 concerns theparticular shape of the camming sector 80 of the engagement controlmember 72. In the engaged state, the cam engaging roller 84 of thepivotal pawl 38 rests upon a step edge 96 of the camming sector 80. Thestep edge 96 is so disposed that a clockwise or disengaging pivot thepawl 38 must act in opposition to the tensional force imposed on theengagement control member 72 by the control member biasing spring 58.

With the pawl 38 firmly engaged the driven member 28 is rotated with thedriving member 26 in a clockwise or first rotational direction, as shownin FIG. 6, until the driven member is subjected to a restraining load,

such as by the second restraining means or stop 44 positioned in itspath of rotation. When the rotation of the driven member 28 isrestrained, as in FIG. 7, the engaging member 40 continues to rotatewith the ratchet wheel 26 in opposition to the biasing force of the armbiasing spring 42 that couples the two members. The coupling ortensioning force of the arm biasing spring 42 can be adjusted so thatdisengagement occurs under any predetermined restraining load imposed onthe driven member 28. When the engaging member 40 continues to rotateclockwise with respect to the driven member 28, the driven membercamming shaft 82 of the engaging member moves into abutment with acamming surface 98 (FIG. 2) of the driven member 28. As the engagingmember 40 continues to rotate clockwise with respect to the restraineddriven member 28, the camming surface 98 of the driven member begins tocam the pivotal pawl 38 clockwise. The relative motion between theengaging member 40 and the driven member 28 causes the cam engagingroller 84 of the pawl 38 to roll over the step edge 96 of the cammingsector and onto the cam engaging edge 86 thereof where the tensioningforce applied to the engagementcontrol member 72 of the control memberbiasing spring 58 cams the pawl 38 clockwise into complete disengagementwith the ratchet wheel 26, as illustrated in FIG. 7..With the pawl 38disengaged the return biasing spring 36 then reinitiates the cycle byrotating the driven member 28 counterclockwise until the stop engagingextension 91 of the engagement control member 72 is restrained in itspivotal displacement by the first restraining means or stop 92,whereupon engagement again occurs. Such reciprocation would continueindefinitely until a cycle is interrupted, such as by the operation ofthe keyed latch 32 and bail 34, as heretofore described.

In the specific application earlier described, where the clutchmechanism is utilized in a printing machine to provide a documentspacing option, the driven member 28 is held by the keyed latch 32 andbail 34 in a home position with the engaging portions 38 of the engagingmember 40 being disengaged from the ratchet wheel 26. Release of thedriven member 28 from the home position allows the return biasing spring36 to pivot the driven member and its associated memberscounterclockwise to initiate engagement of the engaging sector or pawl38. The keyed latch 32 and bail 34 hold the driven member in the homeposition after the engaging pawl has been disengaged from the ratchetwheel 26. A further feature of the clutch mechanism, as applied in adocument spacer option, is a provision for controlled disengagement ofthe pawl 38 from the ratchet wheel 26 whenever the driven member 28 isrotated beyond its home position in the first rotational direction. Thisfeature is accomplished by a reset arm 46 having a bifurcated endcomprised of an upper finger and a lower finger 102, as shown in FIG. 1.Whenever the driven member 28 is driven beyond its home position arestraining lug 104 thereon moves free of the lower surface 106 of theupper finger 100 thus permitting the reset arm 46 to be pivoteddownwardly by a reset actuator such as a solenoid 108. Such a pivotingaction of the reset arm 46 brings a lower edge 110 of the lower finger102 downwardly, thus engaging the projecting end of the driven membercamming shaft 82 that extends from on side of the pawl 38 to pivot thepawl counterclockwise out of engagement with the ratchet 26.

While the invention has been described in. conjunction with a specificembodiment it is evident that many modifications and alterations nottruly departing from the inventive concept residing therein will beapparent to those skilled in the art in light of the foregoingdescription. Accordingly, it is intended to embrace within the appendedclaims all such modifications and alternatives that reside within theinventive concept disclosed herein.

What is claimed is:

1. In combination with a unidirectionally rotatable driving member, therotation thereof being in a first direction, a clutch mechanism forbi-directionally rotating a driven member within a predetermined arc,said mechanism comprising:

first biasing means associated with said driven member and effective forrotating said driven member in a second rotational direction oppositesaid first direction of rotation;

an engaging member bi-directionally rotatable with said driven memberthrough said predetermined are said engaging member having a pivotallymounted engaging portion biased by a torsion biasing means into drivingengagement with said driving member resiliently driving said drivenmember in the first;

second biasing means coupling said engaging member and said drivenmember and effective for rotating said driven member in said firstdirection of rotation as driven by said driving member and said engagingmember; and

an engagement control member bi-directionally rotatable through saidpredetermined arc with said driven member and said engaging member, saidcontrol member being yieldably biased for resilient displacement in thesecond rotational direction with respect to the driven member, saidcontrol member having a camming sector cammably opposed to the engagingportion of said engaging member for maintaining said engaging portionout of driving engagement with said driving member, whereby the relativerotation of said engagement control member in the first rotationaldirection relative to said driven member and said engaging memberreleases the engaging portion of said engaging member into drivingengagement with said driving member while the relative rotation of saiddriven member in the second rotational direction relative to saidengagement member cammably displaces said engaging portion thereof outof engagement with said driving member, the combination of said elementseffectively utilizing the said unidirectional rotation of said drivingmember to produce one of said bi-directional rotations of said drivenmember, said one direction rotation being defined as said firstdirection of rotation.

2. A clutch mechanism as defined in claim 1 further comprising firstrestraint means effective for displacing said engagement control memberin said first rotational direction relative to said driven member andsaid engaging member, and said restraint means effective forrestrainably limiting the first direction rotation of said drivenmember, such restraints being effective to respectively engage anddisengage said engaging portion of said engaging member with saiddriving member.

3 A clutch mechanism as defined in claim 2 wherein said first restraintmeans is a first stop radially disposed in a predetermined location inthe' rotational path of said engagement control member, and said secondrestraint means is a second stop disposed in a predetermined angularlydisplaced location with respect to said first stop, said second stopbeing radially disposed in the rotational path of said driven member,whereby the angular distance between said stops defines saidpredetermined are through which said driven member is bi-dire ctionallyrotated.

4. A clutch mechanism as defined by claim 1 wherein said torsion biasingmeans for biasing said engaging portion of said engaging member intodriving engagement with said driving member is a torsion spring.

5. A clutch mechanism as defined in claim 1 wherein the pivotal axis ofsaid engaging portion is offset from the direction of driving forceimparting to said engaging portion by said driving member so that saiddriving member creates a moment of force about said pivot point tendingto maintain said engaging portion into engagement with said drivingmember.

6. A clutch mechanism as defined in claim 1 wherein the camming sectorof said engagement control member in response to said bias of saidcontrol member.-

cams against a cam engaging means carried by the engaging portion ofsaid engaging member for maintaining said engaging portion out ofdriving engagement with the driving member.

7. A clutch mechanism as defined by claim 6 wherein said camengagingfmeans of said engaging portion is a roller joumaled by saidengaging portion.

8. A clutch mechanism as defined in claim '7 wherein the camming sectorof said engagement control member has a first step-like edge upon whichsaid cam engaging means is biasly maintained during engagement of saidengaging portion with said driving member, the disengaging pivotalmotion of said engaging portion being effective to displace said camengaging means over said first step-like edge onto a second contourededge of said camming sector, said second contoured edge being effectiveto cam said biased engaging portion out of engagement with said drivingmember.

9. A clutch mechanism as defined in claim 8 wherein the disengagingpivotal motion of said engaging portion over the first step-like edge ofsaid camming sector releases said engagement control member to its fullfirst direction displacement so that said camming sector assists inmaintaining said engaging portion disengaged from said driving member.

10. A clutch mechanism as defined in claim 1 wherein said engagingportion has a driven member cam disposed in abutable relationship withsaid driven member for cammably pivoting said engaging portion out ofengagement with said driving member when said driven member is rotatedin the second rotational direction relative to said engaging member.

11. A clutch mechanism as defined in claim 10 wherein said driven membercam is a shaft extending from said engaging portion so that rotation ofsaid a bi-directionally rotatable driven member rotatable torsionbiasing means into driving engagement with said driving member;

second biasing means coupling said engaging member and said drivenmember and effective for rotating said driven member in said firstdirection of rotation as driven by said driving member and said engagingmember;

an engagement control member bi-directionally rotatable with said drivenmember and said engaging member, said control member being biased forresilient displacement in the second rotational direction with respectto the driven member, said control member having a camming sectorcammably opposed to the engaging portion of said engaging member formaintaining said engaging portion out of driving engagement with saiddriving member;

first means for restraining said engagement control member in its seconddirection rotation; and

second means for restraining said driven member in its first directionrotation, such restraint being effective to engage said engaging portionwith said driving member upon restraint of said engagement controlmember and to disengage said engaging portion from said driving memberupon the restraint of said driven member, such that said driven memberserves to lift the document while being rotated in the first rotationaldirection between said first restraining means and said secondrestraining means, said first biasing means being effective to returnsaid driven member in the second rotational direction after the drivenmember is restrained by said second restraining means. 13. A clutchmechanism as defined in claim 12 wherein said first restraining means isa first stop radially disposed in a predetermined location in therotational path of said engagement control member, and,

said second restraining means is a second stop disposed in apredetermined angularly displaced location with respect to said firststop, said second stop being radially disposed in the rotational path ofsaid driven member wherebtyl the angular distance between said stopsdetermines e vertical distance over which the document may be lifted.

14. A clutch mechanism as defined by claim 13 further including meansengageable with said driven member for stopping said driven member in anintermediate position between said first and said second stops, therelease of said driven member by said means being effective to enablesaid first biasing means to rotate said driven member in the secondrotational direction.

15. A clutch mechanism as defined by claim 14 wherein said engageablemeans is characterized by a manually depressible keyed latch and a bail,said bail being restrainingly engageable with said driven member andsaid latch being effective to controllably actuate said bail.

16. A clutch mechanism as defined in claim 12 wherein said drivenmember, said engaging member and said engagement control member arebidirectionally rotatable about an axis common with the axis of saiddriving member,

17. A clutch mechanism as defined in claim 12 further comprising aratchet wheel fixedly connected to the driving member for rotationtherewith.

18. A clutch mechanism as defined in claim 17 wherein the engagingportion of said engaging member has a tooth for engagement with saidratchet wheel.

1: r a: 1: a:

32230 Uri-TED STATES PATENT OFFICE. CERTIFICATE OF CORRECTION Patent No.3,7 3, 9 Dated November 28, 1972 Ronald H. Mack, Robert H. Wilozewskiand Invenzofls) Nicholas Kondur, Jr.

It is certified that error appears in the-above-identified patent andthat said Letters Patent are hereby corrected as shown below:

Col. 7, lines 28 and 29, delete "resiliently driving said.

driven member in the first? Signed and sealed this 1st day of May 1973.

(SEAL) Attest:

EDEETARQM. FlElCHER, JR. ROBERT GOTTSCHALK At testing OfficerCommissioner of Patents

1. In combination with a unidirectionally rotatable driving member, therotation thereof being in a first direction, a clutch mechanism forbi-directionally rotating a driven member within a predetermined arc,said mechanism comprising: first biasing means associated with saiddriven member and effective for rotating said driven member in a secondrotational direction opposite said first direction of rotation; anengaging member bi-directionally rotatable with said driven memberthrough said predetermined arc said engaging member having a pivotallymounted engaging portion biased by a torsion biasing means into drivingengagement with said driving member resiliently driving said drivenmember in the first; second biasing means coupling said engaging memberand said driven member and effective for rotating said driven member insaid first direction of rotation as driven by said driving member andsaid engaging member; and an engagement control member bi-directionallyrotatable through said predetermined arc with said driven member andsaid engaging member, said control member being yieldably biased forresilient displacement in the second rotational direction with respectto the driven member, said control member having a camming sectorcammably opposed to the engaging portion of said engaging member formaintaining said engaging portion out of driving engagement with saiddriving member, whereby the relative rotation of said engagement controlmember in the first rotational direction relative to said driven memberand said engaging member releases the engaging portion of said engagingmember into driving engagement with said driving member while therelative rotation of said driven member in the second rotationaldirection relative to said engagement member cammably displaces saidengaging portion thereof out of engagement with said driving member, thecombination of said elements effectively utilizing the saidunidirectional rotation of said driving member to produce one of saidbi-directional rotations of said driven member, said one directionrotation being defined as said first direction of rotation.
 2. A clutchmechanism as defined in claim 1 further comprising first restraint meanseffective for displacing said engagement control member in said firstrotational direction relative to said driven member and said engagingmember, and said restraint means effective for restrainably limiting thefirst direction rotation of said driven member, such restraints beingeffective to respectively engage and disengage said engaging portion ofsaid engaging member with said driving member.
 3. A clutch mechanism asdefined in claim 2 wherein said first restraint means is a first stopradially disposed in a predetermined location in the rotational path ofsaid engagement control member, and said second restraint means is asecond stop disposed in a predetermined angularly displaced locationwith respect to said first stop, said second stop being radiallydisposed in the rotational path of said driven member, whereby theangular distance between said stops defines said predetermined arcthrough which said driven member is bi-directionally rotated.
 4. Aclutch mechanism as defined by claim 1 wherein said torsion biasingmeans for biasing said engaging portion of said engaging member intodriving engagement with said driving member is a torsion spring.
 5. Aclutch mechanism as defined in claim 1 wherein the pivotal axis of saidengaging portion is offset from the direction of driving force impartingto said engaging portion by said driving member so that said drivingmember creates a moment of force about said pivot point tending tomaintain said engaging portion into engagement with said driving member.6. A clutch mechanism as defined in claim 1 wherein the camming sectorof said engagement control member in response to said bias of saidcontrol member cams against a cam engaging means carried by the engagingportion of said engaging member for maintaining said engaging portionout of driving engagement with the driving member.
 7. A clutch mechanismas defined by claim 6 wherein said cam engaging means of said engagingportion is a roller journaled by said engaging portion.
 8. A clutchmechanism as defined in claim 7 wherein the camming sector of saidengagement control member has a first step-like edge upon which said camengaging means is biasly maintained during engagement of said engagingportion with said driving member, the disengaging pivotal motion of saidengaging portion being effective to displace said cam engaging meansover said first step-like edge onto a second contoured edge of saidcamming sector, said second contoured edge being effective to cam saidbiased engaging portion out of engagement with said driving member.
 9. Aclutch mechanism as defined in claim 8 wherein the disengaging pivotalmotion of said engaging portion over the first step-like edge of saidcamming sector releases said engagement control member to its full firstdirection displacement so that said camming sector assists inmaintaining said engaging portion disengaged from said driving member.10. A clutch mechanism as defined in claim 1 wherein said engagingportion has a driven member cam disposed in abutable relationship withsaid driven member for cammably pivoting said engaging portion out ofengagement with said driving member when said driven member is rotatedin the second rotational direction relative to said engaging member. 11.A clutch mechanism as defined in claim 10 wherein said driven member camis a shaft extending from said engaging portion so that rotation of saiddriven member in the second direction relative to said engaging membercauses said driven member to cammably contact said shaft and to pivotsaid engaging portion out of engagement with said driving member.
 12. Ina printing machine having a paper strip feeding apparatus, including aunidirectionally rotatable driving member for vertically spacing thestrip according to the printed lines thereon, a clutch mechanismcooperating with said paper strip feeding apparatus for likewise spacinga document within a predetermined vertical distance, said mechanismcomprising: a bi-directionally rotatable driven member rotatable in afirst direction for vertically spacing the document over thepredetermined vertical distance according to a predetermined variablenumber of printed lines that are to be provided thereon; first biasingmeans associated with said driven member and effective for rotating saiddriven member in a second rotational direction; an engaging memberbi-directionally rotatable wIth said driven member, said engaging memberhaving a pivotally mounted engaging portion biased by a torsion biasingmeans into driving engagement with said driving member; second biasingmeans coupling said engaging member and said driven member and effectivefor rotating said driven member in said first direction of rotation asdriven by said driving member and said engaging member; an engagementcontrol member bi-directionally rotatable with said driven member andsaid engaging member, said control member being biased for resilientdisplacement in the second rotational direction with respect to thedriven member, said control member having a camming sector cammablyopposed to the engaging portion of said engaging member for maintainingsaid engaging portion out of driving engagement with said drivingmember; first means for restraining said engagement control member inits second direction rotation; and second means for restraining saiddriven member in its first direction rotation, such restraint beingeffective to engage said engaging portion with said driving member uponrestraint of said engagement control member and to disengage saidengaging portion from said driving member upon the restraint of saiddriven member, such that said driven member serves to lift the documentwhile being rotated in the first rotational direction between said firstrestraining means and said second restraining means, said first biasingmeans being effective to return said driven member in the secondrotational direction after the driven member is restrained by saidsecond restraining means.
 13. A clutch mechanism as defined in claim 12wherein said first restraining means is a first stop radially disposedin a predetermined location in the rotational path of said engagementcontrol member, and said second restraining means is a second stopdisposed in a predetermined angularly displaced location with respect tosaid first stop, said second stop being radially disposed in therotational path of said driven member whereby the angular distancebetween said stops determines the vertical distance over which thedocument may be lifted.
 14. A clutch mechanism as defined by claim 13further including means engageable with said driven member for stoppingsaid driven member in an intermediate position between said first andsaid second stops, the release of said driven member by said means beingeffective to enable said first biasing means to rotate said drivenmember in the second rotational direction.
 15. A clutch mechanism asdefined by claim 14 wherein said engageable means is characterized by amanually depressible keyed latch and a bail, said bail beingrestrainingly engageable with said driven member and said latch beingeffective to controllably actuate said bail.
 16. A clutch mechanism asdefined in claim 12 wherein said driven member, said engaging member andsaid engagement control member are bi-directionally rotatable about anaxis common with the axis of said driving member,
 17. A clutch mechanismas defined in claim 12 further comprising a ratchet wheel fixedlyconnected to the driving member for rotation therewith.
 18. A clutchmechanism as defined in claim 17 wherein the engaging portion of saidengaging member has a tooth for engagement with said ratchet wheel.